A good night's sleep is vital to health and happiness, yet many people are deprived of sleep by the habitual snoring of a bed partner. Various solutions have been introduced in attempts to lessen the burden imposed on bed partners by habitual snoring. Medicines and mechanical devices are sold over the counter and the Internet. Medical remedies include surgical alteration of the soft palette and the use of breathing assist devices. Noise generators may also be used to mask snoring and make it sound less objectionable.
Various devices have been proposed to cancel, rather than mask, snoring. One such device, proposed in U.S. Pat. No. 5,444,786, uses a microphone and acoustic speaker placed immediately in front of a snorer's nose and mouth to cancel snoring at the source. However, canceling sound can propagate and be obtrusively audible to the snorer and others. A device discussed in U.S. Pat. No. 5,844,996 uses continuous feedback control to cancel snoring sounds. A microphone close to a snorer's nose and mouth records snoring sounds and speakers proximate to a bed partner broadcast snore canceling sounds that are controlled via feedback determining microphones adhesively taped to the face of the bed partner. U.S. Pat. No. 6,368,287 discusses a face adherent device for sleep apnea screening that comprises a microphone, processor and battery in a device that is adhesively attached beneath the nose to record respiration signals. Attaching devices to the face can be physically discomforting to the snorer as well as psychologically obtrusive to snorer and bed partner alike, leading to reduced patient compliance.
Methods of canceling sound without feedback control have been implemented where the positions of source and the outlet of sound are close together and fixed, such as in U.S. Pat. No. 6,330,336, which proposes co-emitted anti-phase noise used in a photocopier to cancels the sound of an internal fan. In another example, noise-canceling earphones proposed in U.S. Pat. No. 5,305,587 detect environmental noise and broadcast a canceling signal in a fixed relationship to the ear.